This invention relates generally to a radial piston pump having at least two pumping elements. More particularly, this invention relates to a radial piston pump for use in connection with hydraulic clamping devices in machine tools.
In prior-art radial piston pumps of this type, when the clamping cylinder has attained its working or clamping position, the entire flow of pressure fluid discharged from the pump has to be returned to a reservoir or tank via a pressure limiting valve so that the final working position of the clamping cylinder be maintained. Accordingly, this clamping process results in an uneconomical operation of the pump. In addition, by returning the delivered pressure fluid through the pressure limiting valve which determines the holding force for the clamping device, fluid is heated and has to be again cooled to a prescribed working temperature.